Disposable absorbent article having side panels with structurally, functionally and visually different regions

ABSTRACT

A disposable absorbent article worn about the lower torso of a wearer includes at least one pair of side panels connecting a first waist region to a second waist region forming a waist opening and a pair of leg openings. Each side panel includes a waist region, a hip region and a leg region wherein the waist region, the hip region and the leg region differs structurally, functionally, and visually to provide an improved initial fit and sustained fit while exhibiting a garment-like appearance.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 13/071,776,filed Mar. 25, 2011 which is a continuation of application Ser. No.12/199,927, filed Aug. 28, 2008, now U.S. Pat. No. 7,919,669 which is acontinuation of application Ser. No. 11/303,686, filed Dec. 16, 2005,now U.S. Pat. No. 7,432,413 the substance of which is incorporatedherein by reference.

FIELD OF THE INVENTION

This invention is directed to hygienic absorbent articles, such asdiapers, pant style diapers, training pants and the like. Particularly,the invention is directed to such hygienic absorbent articles havingside panels including regions that differ structurally, functionally andvisually.

BACKGROUND OF THE INVENTION

Infants and other incontinent individuals wear absorbent articles suchas diapers to receive and contain urine and other body exudates.Absorbent articles function both to contain the discharged materials andto isolate these materials from the body of the wearer and from thewearer's garments and bed clothing.

Diaper manufacturers have attempted to improve the appearance andfunction of diapers by providing a more garment like look and improvingfit by introducing stretch. However, often times the featuresinfluencing fit adversely affect the appearance. For instance,disposable diapers with side stretch features have used stretch andforce profiles to provide good initial fit as well as good sustainedfit. Disposable diapers offering such side stretch features are oftenmultipiece designs composed of diaper chassis with stretchable sidepanels bonded to and extending from at least one of the longitudinalside edges. Such multipiece designs often appear less garments-like andrequire decorative features to compensate. In addition, the bondextending parallel to the longitudinal side edges of the diaper causesforces to be very similar or equal along the stretch panel from top tobottom when the diaper is applied on a wearer. The equal forces resultin either red marking of the skin at the top of the leg, poor sustainedfit about the waist, or both. In addition, the edges of the side panelstend to fold or roll inward toward the center of the side panelexhibiting a poor fit that appears less garment-like.

Therefore, it is an object of the present invention to provide adisposable absorbent article capable of providing improved initial fit,sustained fit, and reduced red marking of the wearer's skin whileappearing more garment-like.

SUMMARY OF THE INVENTION

The present invention provides a disposable absorbent article to be wornabout the lower torso of a wearer. The disposable absorbent articleincludes at least one pair of side panels connecting a first waistregion to a second waist region forming a waist opening and a pair ofleg openings. Each side panel includes a waist region, a hip region anda leg region wherein the waist region, the hip region and the leg regiondiffer structurally, functionally and visually to provide an improvedinitial fit and a sustained fit while exhibiting a garment-likeappearance.

In one embodiment, a pair of side panels is disposed in the second waistregion. Each side panel includes a waist region, a hip region and a legregion, where the waist, hip and leg regions differ structurally,functionally and visually. Each side panel also includes a fastener forreleasably attaching the side panel to the first waist region.

In another embodiment, a first pair of side panels is attached to thesecond waist region and second pair of side panels is attached to thefirst waist region. The first pair of side panels is attached to thesecond pair of side panels forming a pant having a waist opening and apair of leg openings. Each pair of side panels includes a waist region,a hip region and a leg region wherein the waist region, hip region andthe leg region differ structurally, functionally, and visually.

BRIEF DESCRIPTION OF THE DRAWINGS

While this specification concludes with claims particularly pointing outand distinctly claiming that which is regarded as forming the presentinvention, it is anticipated that the invention can be more readilyunderstood through reading the following detailed description of theinvention and study of the accompanying drawings.

FIG. 1 is a plan view of a disposable diaper constructed in accordancewith the present invention having portions cut away to reveal underlyingstructure. The body-facing surface of the diaper is facing the viewer.

FIG. 2 is a plan view of side panel attached to the disposable diaper inFIG. 1.

FIG. 3 is an isometric view of the diaper in FIG. 1 configured in afitted orientation.

FIG. 4 is an isometric view of a pant style diaper constructed inaccordance with the present invention.

FIG. 5 is an exemplary stress-strain curve showing “Available Strain”.

DETAILED DESCRIPTION OF THE INVENTION

Definitions

As used herein, the following terms have the following meanings:

“Absorbent article” refers to devices that absorb and contain liquid,and more specifically, refers to devices that are placed against or inproximity to the body of the wearer to absorb and contain the variousexudates discharged from the body.

“Longitudinal” is a direction running parallel to the maximum lineardimension of the article and includes directions within ±45° of thelongitudinal direction.

The “lateral” or “transverse” direction is orthogonal to thelongitudinal direction.

The “Z-direction” is orthogonal to both the longitudinal and transversedirections.

The “x-y plane refers to the plane congruent with the longitudinal andtransverse directions.

As used herein, the term “disposed” is used to mean that an element(s)is formed (joined and positioned) in a particular place or position as aunitary structure with other elements or as a separate element joined toanother element.

As used herein, the term “joined” encompasses configurations whereby anelement is directly secured to another element, by affixing the elementdirectly to the other element, and configurations whereby an element isindirectly secured to another element by affixing the element tointermediate member(s) which in turn are affixed to the other element.

A “unitary” absorbent article refers to absorbent articles which areformed of separate parts united together to form a coordinated entity sothat they do not require separate manipulative parts like a separateholder and liner.

The terms “permeable” and “impermeable” refer to the penetrability ofmaterials in the context of the intended usage of disposable absorbentarticles. Specifically, the term “permeable” refers to a layer or alayered structure having pores or openings that permit liquid water topass through its thickness in the absence of a forcing pressure.Conversely, the term “impermeable” generally refers to articles and/orelements that are not penetrative by fluid through the entireZ-directional thickness of the article under pressure of 0.14 lb/in² orless. Preferably, the impermeable article or element is not penetrativeby fluid under pressures of 0.5 lb/in² or less. More preferably, theimpermeable article or element is not penetrative by fluid underpressures of 1.0 lb/in² or less.

The term “attached” refers to elements being connected or united byfastening, adhering, bonding, etc. by any method suitable for theelements being fastened, secured, or joined, together and theirconstituent materials. Many suitable methods for attaching elementstogether are well-known, including adhesive bonding, pressure bonding,thermal bonding, mechanical fastening, etc. Such attachment methods maybe used to attach elements together over a particular area eithercontinuously or intermittently. The term “attached” includes elementswhich are integrally formed with another element.

The terms “corrugations” or “rugosities” are used to describe hills andvalleys that occur in a substrate or in a laminated structure. Neitherterm, i.e. “corrugations” nor “rugosities”, mandates that either thehills or valleys created are uniform in nature.

As used herein, the term “diaper” refers to an absorbent articlegenerally worn by infants and incontinent persons about the lower torsoso as to encircle the waist and legs of the wearer and that isspecifically adapted to receive and contain urinary and fecal waste. Asused herein, term “diaper” also includes “pants” which is defined below.

The term “disposable” is used herein to describe absorbent articles thatgenerally are not intended to be laundered or otherwise restored orreused as absorbent articles (i.e., they are intended to be discardedafter a single use and, preferably, to be recycled, composted orotherwise discarded in an environmentally compatible manner).

As used herein “elastically extensible” refers to characteristics ofextensible materials that have the ability to return to approximatelytheir original dimensions after a force that extended the extensiblematerial is removed. Herein, any material or element described as“extensible” may also be “elastically extensible” unless otherwiseprovided.

As used herein the term “stretch” means to forcibly extend in length orwidth.

“Live stretch” includes stretching elastic and bonding the stretchedelastic to a nonwoven. After bonding the stretched elastic is releasedcausing it to contract, resulting in a “corrugated” nonwoven. Thecorrugated nonwoven can stretch as the corrugated portion is pulled toabout the point that the nonwoven reaches at least one original flatdimension. The elastic is preferably stretched at least 25% and morepreferably at least 100% of its relaxed length when it is bonded to thenonwoven.

The terms “pant”, “pant style diaper”, “training pant”, “closed diaper”,“pre-fastened diaper”, and “pull-on diaper”, as used herein, refer todisposable garments having a waist opening and leg openings designed forinfant or adult wearers. A pant can be configured such that the pant hasa closed waist and leg openings prior to being donned on the wearer orthe pant can be configured such that the waist is closed and the legopenings are formed while on the wearer. A pant may be preformed by anysuitable technique including, but not limited to, attaching togetherportions of the article using refastenable and/or non-refastenable bonds(e.g., seam, weld, adhesive, cohesive bond, fastener, etc.). A pant maybe preformed anywhere along the circumference of the article (e.g., sidefastened, front waist fastened, rear waist fastened). Examples ofsuitable pants are disclosed in U.S. Pat. Nos. 5,246,433; 5,569,234;6,120,487; 6,120,489; 4,940,464; 5,092,861; 5,897,545; 5,957,908; andU.S. Patent Publication No. 2003/0233082 A1.

Description:

Wearable articles constructed in accordance with the present inventionhave a pair of side panels where each side panel includes regions thatdiffer visually, structurally or functionally. The side panels areequally applicable to wearable articles such as disposable absorbentarticles including diapers, pant style diapers, training pants,incontinence briefs, incontinence undergarments, absorbent inserts,diaper holders and liners, feminine hygiene garments, and the like. Oneembodiment of an absorbent article of the present invention is a unitarydisposable absorbent article, such as the diaper 20, shown in FIG. 1.

FIG. 1 is a plan view of the diaper 20 of the present invention in aflat-out state with portions of the structure being cut-away to moreclearly show the construction of the diaper 20. The portion of thediaper 20 which faces the wearer is oriented towards the viewer. Thediaper 20 has a first waist region 36, a second waist region 38 opposedto the first waist region 36 and a crotch region 37 located between thefirst waist region 36 and the second waist region 38. The periphery ofthe diaper 20 is defined by the outer edges of the diaper 20 in whichlongitudinal edges 50 run generally parallel to the longitudinalcenterline 100 of the diaper 20 and end edges 52 run between thelongitudinal edges 50 generally parallel to the lateral centerline 110of the diaper 20.

As shown in FIG. 1, the diaper 20 comprises a liquid pervious topsheet24; a liquid impervious backsheet 26; an absorbent core 28 which ispreferably positioned between at least a portion of the topsheet 24 andthe backsheet 26; side panels 30; extensible leg cuffs 32, elastic waistfeatures 34 and a fastening system generally designated 40. The chassis22 of the diaper 20 comprises the main body of the diaper 20 andincludes the topsheet 24 and/or the backsheet 26 and at least a portionof the absorbent core 28. While the topsheet 24, the backsheet 26, theabsorbent core 28, side panels 30 and other aforementioned constituentsmay be assembled in a variety of well known configurations, preferreddiaper configurations are described generally in U.S. Pat. No. 3,860,003entitled “Contractible Side Portions for Disposable Diaper” issued toKenneth B. Buell on Jan. 14, 1975; U.S. Pat. No. 5,151,092 issued toBuell on Sep. 9, 1992; and U.S. Pat. No. 5,221,274 issued to Buell onJun. 22, 1993; and U.S. Pat. No. 5,554,145 entitled “Absorbent ArticleWith Multiple Zone Structural Elastic-Like Film Web Extensible WaistFeature” issued to Roe et al. on Sep. 10, 1996; U.S. Pat. No. 5,569,234entitled “Disposable Pull-On Pant” issued to Buell et al. on Oct. 29,1996; U.S. Pat. No. 5,580,411 entitled “Zero Scrap Method forManufacturing Side Panels for Absorbent Articles” issued to Nease et al.on Dec. 3, 1996; and U.S. Pat. No. 6,004,306 entitled “Absorbent ArticleWith Multi-Directional Extensible Side Panels” issued to Robles et al.on Dec. 21, 1999.

The side panels 30 can have a number of different sizes and shapes, butpreferably have a trapezoidal shape. The side panels 30 can be elasticor extensible to provide a more comfortable and contouring fit byinitially conformably fitting the diaper 20 to the wearer and sustainingthis fit throughout the time of wear. Side-panels 30 which areelasticized can provide a sustained fit well past when the diaper 20 hasbeen loaded with exudates since the elasticized side panels 30 allow thesides of the diaper 20 to expand and contract. The side panels 30 mayalso provide more effective application of the diaper 20 because even ifone elasticized side panel 30 is pulled farther than the other duringapplication, the diaper 20 will “self-adjust” during wear.

The side panels 30 may comprise a separate element affixed to thechassis 22, or can be constructed as an extension of other elements ofthe diaper such as the backsheet 26 or the topsheet 24, preferably boththe topsheet 24 and the backsheet 26. In the embodiment shown in FIG. 1,the side panels 30 each comprise a separate web joined to the chassis 22in the second waist region 38 and extend laterally outwardly beyond thelongitudinal edges 50. The side panels 30 comprise a first end edge 90positioned adjacent the end edge 52 of the diaper, a second end edge 92positioned away from the first end edge 90 towards the lateralcenterline 110, a first longitudinal edge 94 attached to thelongitudinal edge 50, and a second longitudinal edge 96 positionedlaterally outwardly from the longitudinal edge 50. The firstlongitudinal edge 94 may be contiguous with the longitudinal edge 50,preferably the first longitudinal edge 94 is positioned laterallyinwardly of the longitudinal edge 50. The side panels 30 may include anonelastic extension members 42 attached to the second longitudinaledges 96 and fasteners 40 attached to the nonelastic extension members42. The nonelastic extension members 42 can be made to distribute theshear forces along the second longitudinal edges 96 of the side panels30 during fastening.

While the diaper 20 shown in FIG. 1 has the side panels 30 disposed inthe second waist region 38, the diaper 20 may be provided with sidepanels 30 disposed in the first waist region 36 or in both the firstwaist region 36 and the second waist region 38. The side panels 30 maybe constructed in any suitable configurations. Examples of diapers withelasticized side panels are disclosed in U.S. Pat. No. 4,857,067,entitled “Disposable Diaper Having Shirred Ears” issued to Wood, et al.on Aug. 15, 1989; U.S. Pat. No. 4,381,781 issued to Sciaraffa, et al. onMay 3, 1983; U.S. Pat. No. 4,938,753 issued to Van Gompel, et al. onJul. 3, 1990; the herein before referenced U.S. Pat. No. 5,151,092issued to Buell on Sep. 9, 1992; U.S. Pat. No. 5,221,274 issued to Buellon Jun. 22, 1993; U.S. Pat. No. 5,669,897 issued to LaVon, et al. onSep. 23, 1997 entitled “Absorbent Articles Providing Sustained DynamicFit”; and U.S. Pat. No. 6,004,306 entitled “Absorbent Article WithMulti-Directional Extensible Side Panels” issued to Robles et al. onDec. 21, 1999.

The side panels 30 of the present invention include separate regionswhere each region differs structurally, functionally or visually. Forinstance, the side panel shown in FIG. 2 includes three regions, a waistregion 80, a hip region 82 and a leg region 84. The waist region 80 islocated near end edge 52 and can extend from the first longitudinal edge94 to the second longitudinal edge 96. The leg region 84 is located nearthe longitudinal edge 50 and can extend from the first longitudinal edge94 to the second longitudinal edge 96. The hip region 82 is locatedbetween the waist, region 80 and the leg region 84 and can extend fromthe first longitudinal edge 94 to the second longitudinal edge 96. Thearea of the side panel 30 occupied by each of the regions may vary;however, the hip region can cover 40%-90%, preferably 60%-80% of theside panel surface area, while the waist region can cover, 5%-30%,preferably 10%-20% of the side panel surface area and the leg region cancover, 5%-30%, preferably 10%-20% of the side panel surface area.

Each of the waist, hip and leg regions 80, 82, 84 can differ from theother two regions either structurally, functionally or visually. In oneembodiment, each of the three regions differs from the other two regionsstructurally and visually. In another embodiment, each of the threeregions can differ from the other two regions functionally and visually.In another embodiment, each of the three regions can differ from theother two regions structurally and functionally. In yet anotherembodiment, each of the three regions can differ from the other tworegions structurally, functionally, and visually. Further, in anotherembodiment, any two regions may be the same but differ from the thirdregion structurally, functionally or visually. In still anotherembodiment, any two regions may be structurally, functionally, andvisually the same but differ from the third region structurally,functionally and visually.

Structural differences between the waist region 80, hip region 82, andleg region 84 can include differences in types of materials used;activation patterns in zero-strain elastomeric laminates; materialthicknesses; bonding patterns; layers of materials and combinationsthereof. Structural differences between the waist region 80, hip region82, and leg region 84 of the side panel 30 can be made to accentuate thevisual distinctiveness between the regions, affect the functionalattributes of the regions or both.

Functional differences between the waist region 80, hip region 82, andleg region 84 of the side panel 30 can be made to influence how thediaper 20 fits on a wearer. Functional differences can includedifferences in stiffness, bending modulus, elastic modulus,extensibility, force relaxation, set, recovery rate, torsional modulus,compression modulus, compressibility, coefficient of friction, surfaceenergy and combinations thereof.

The side panels 30 may be constructed from a number of differentmaterials. For instance, the side panels may comprise conventionalelastic materials or stretch laminates. The stretch laminates maycomprise a laminated structure known as live stretch, previouslydefined, where an elastic element is attached to a substrate while theelastic element is under strain; such that once the strain is relievedthe laminate forms corrugations or gathers and exhibits a shirredstructure having elastic-like properties.

Alternatively, the stretch laminate may comprise a mechanicallyactivated stretched laminate such as a zero strain stretch laminate.Zero strain stretch laminates comprise a laminated structure whichincludes a first substrate, a second substrate and an elastic element.The first substrate and the second substrate, which are typicallynon-elastic nonwovens, are attached to the elastic element in a face toface orientation such that the elastic element is sandwiched between thefirst substrate and the second substrate. The laminated structure ismechanically activated enabling it to stretch. Mechanical activationrefers to a process wherein the nonwoven fibers of the non-elasticsubstrates are broken, and/or stretched, within the nonwoven so that thenonwoven is stretched in a direction along its surfaces and can beeasily expanded in that direction by partial straightening of the fibersin the nonwoven. Zero-strain elastomeric laminates are described in U.S.Pat. No. 5,143,679 issued to Weber et al., U.S. Pat. No. 5,156,793issued to Buell et al., and U.S. Pat. No. 5,167,897 issued to Weber.

The elastic element used in the side panels 30 can include elasticstrands or elastic films. Any suitable elastic film known in the art canbe used. Suitable elastic films may comprise polypropylene,polyethylene, polyolefins, styrene-isoprene-styrene,styrene-butadiene-styrene, or combinations thereof. The basis weight ofthe films can range from about 10 gsm to about 100 gsm.

Suitable elastic strands can be made of a resilient elasticthermoplastic material. The elastic strands may be made from liquidelastic that is extruded through a die to achieve the desired strandelastic diameter and/or shape. The shape of the extruded elastic strandsis not limited. For example, typical elastic strands have a circularcross sectional shape, but sometimes the elastic strands may havedifferent shapes, such as a trilobal shape, or a flat (i.e., “ribbon”like) shape. Suitable elastic strand shapes include rectangles, circles,ellipses, diamonds, triangles, parallelograms, trapezoids, wedges orother sections of circles or ellipses, other polygons, or otherirregular enclosed shapes. Furthermore, the thickness or diameter of theelastic strands may vary in order to accommodate a particularapplication. Typically, the thickness of elastic strands may be in therange of about 0.02 mm to about 1 mm and the basis weight is in therange of about 20 g/m² to about 300 g/m².

The elastic strands can be adhesively attached to the substrate,extruded onto the substrate, or printed onto the substrate. Suitableapparatuses for applying elastic strands in a longitudinal direction aredescribed in U.S. Publication No. 2004/0238105 A1 and in U.S.application Ser. No. 10/836,944 entitled “Apparatus for Producing.Elastomeric Nonwoven Laminates” filed on Apr. 30, 2004. Apparatuses forapplying elastic strands in a transverse direction, an angle from thelongitudinal direction, or in a curvilinear fashion are described inU.S. Publication No. US 2005-0178494 A1 entitled “Method of PlacingMaterial Transversely on a Moving Web” filed on Feb. 13, 2004.Apparatuses for applying elastic strands in the longitudinal direction,an angle from the longitudinal direction, or in a curvilinear fashionare described in U.S. application Ser. No. 10/834,539 entitled“Extrusion Applicator Having Linear Motion Operability” filed on Apr.29, 2004, and in U.S. application Ser. No. 10/834,503 entitled“Extrusion Applicator Having Rotational Operability” filed on Apr. 29,2004.

Suitable apparatuses and methods for printing elastic elements in anyorientation are described in U.S. Publication No. 2004-0181200A1entitled “Variable Stretch Composites and Methods of Making theComposite” filed on Mar. 29, 2004, and in U.S. Publication No.2004-0193133A1 entitled “Variable Stretch Composites and Methods ofMaking the Composite” filed on Mar. 29, 2004. For the printing ofelastic strands, the individual elastic strands may be configured aslines or strands generally having widths less than about 2 mm andtypically less than about 1 mm. Linear elastic strands may be configuredas bands generally having widths between about 2 mm and about 20 mm andaspect ratios ranging from about 2:1 to about 100:1. Typically, thethickness of an elastic strand may be in the range of about 0.02 mm toabout 5 mm and the basis weight is in the range of about 20 g/m² toabout 300 g/m².

The first or second substrates forming the side panels may comprisewoven materials, nonwoven materials, combinations of woven and nonwovenmaterials, or laminated structures having woven or nonwoven materials.Suitable nonwoven materials for use in accordance with the presentinvention may comprise fibers made of polypropylene, polyethylene,polyester, nylon, cellulose, polyamide, or combinations of suchmaterials. Fibers of one material or fibers of different materials ormaterial combinations may be used in the nonwovens. Suitable processesfor manufacturing nonwoven materials include spunbond, spunbondmeltblown spunbond (SMS), spunbond meltblown meltblown spunbond (SMMS),carded and the like. Other suitable nonwoven materials include highelongation carded (HEC) nonwovens and deep activation polypropylene(DAPP) nonwovens. Any process known in the art may be used to make thenonwovens. The basis weight of the first nonwoven and/or second nonwovenmay, for example, be in the range of about 10 gsm to about 40 gsm.

The first substrate, second substrate and the elastic element may beattached by any means of attachment known in the art. Suitable attachingmeans and/or methods for attaching include, but are not limited to,adhesives, cohesives, thermal bonding, pressure bonding, mechanicalbonding, ultrasonic bonding, and/or any combination of any known methodsof attaching such materials.

Structural differences between the waist region 80, hip region 82, andleg region 84 of the side panels 30 may include the use of differentelastomeric elements in the waist region 80 and/or leg region 84 versusthe hip region 82 resulting in differences in functional properties andvisual appearance based on the properties of the individual materials.For instance, a zero-strain elastomeric laminate side panel may includeelastic elements attached under tension to the waist region 80 and legregion 84 of the side panels 30 producing a greater number of rugositieswhich are greater in size when relaxed than zero-strain stretchlaminates in the hip region 82 causing visual distinctions which makethem appear as garment-like seams while at the same time providegripping or applications aids. Alternatively, different activationpatterns among the regions may yield visually different regions withdifferent maximum elongations and/or stress/strain properties. Likewise,variations in bonding patterns between layers in the regions may affectthe stress/strain properties and the frequency and/or size of rugositiesin the region.

Other Examples of side panels 30 constructed with a structurallydifferent waist region 80, hip region 82, and leg region 84 resulting infunctional differences among the regions and methods of forming the sameare provided below.

In one embodiment, the structural differences may result in the elasticmodulus of the hip region 82 being higher than elastic modulus of thewaist and/or leg regions 80, 84, enabling the hip region 82 to carrymore of the anchoring load. This can lead to reduced marking and reducedtendency of any attached fastener to curl under side panel tension.Alternatively, the elastic modulus may be higher in the waist and/or legregions 80, 84 versus the hip region 82 if increased gasketing orperimeter edge control is required.

In another embodiment, the structural differences may involveextensibility where the extensibility of the waist and/or leg regions80, 84 may be greater than that of the hip region 82 so as to allow thewaist and legs to move freely without binding, reducing the potentialfor red marking. Alternatively, the waist and/or leg regions 80, 84 maybe less extensible than the hip region 82 to better gasket and protectagainst waste leakage.

Differences in the elastic modulus and stretchability between the waist,hip and leg regions 80, 82, 84 can be affected by including structuraldifferences in the regions impacting these properties.

For instance, a zero strain stretch laminate side panel can bemechanically activated by meshing the side panel between first andsecond activation rolls each of which comprises a plurality of teeth.The teeth of the first activation roll intermesh with the teeth of thesecond activation roll. Structural differences between the waist hip andleg regions 80, 82, 84 can be attained by mechanically activatingportions of the side panel to different percentages of strain. Thepercentage strain experienced by the side panel regions depends on thedepth of engagement between the intermeshing teeth of the firstactivation roll and the teeth of the second activation roll. Activatingportions of the side panel at smaller depths of engagement (e.g. shorterteeth) results in different functional characteristics as compared toportions activated at larger depths of engagement. The portions exposedto the smaller depths of engagement experience smaller percentages ofstrain making them less elastically extensible. For example, a portionof a side panel which was strained to 200% may be able to elasticallyextend up to about three times its original length. However, a portionwhich was strained to 500% may be able to elastically extend up to aboutsix times its original length.

In an alternate embodiment, a side panel may comprise a plurality ofelastic elements attached to a substrate. The functional differences canbe attained by altering the spacing of the plurality of elasticelements. For example, the spacing between each of the of elasticelements in the waist region 80 and the leg region 84 may be about 2 mmwhile the spacing between each of the plurality of elastic elements inthe hip region 82 may be about 1 mm. Alternatively, the spacing betweeneach of the elastic elements in the waist region 80, leg region 84 andwaist region 82 can differ. For instance, the spacing between theelastic elements in the waist region 80 may be 1 mm, while the spacingbetween the elastic elements in the hip region 82 is 2 mm and thespacing between the elastic elements in the leg region is 3 mm. Assumingthe plurality of elastic elements has the same physical and chemicalproperties in the waist, leg, and the hip regions 80, 84, 82, theelastic modulus in each of the regions can differ relative to thespacing.

In another embodiment, structural differences resulting in functionaldifferences such as elastic modulus and/or stretchability can beattained by altering the properties of a plurality of elastic elements.For instance, a plurality of elastic elements in the waist region 80,can have different physical or chemical properties than the physical orchemical properties of a plurality of elastic elements in the leg region84 and both the waist and leg regions 80, 84 can have different physicalor chemical properties than the physical or chemical properties of aplurality of elastic elements in the in a hip region 82. For instance, aplurality of elastic elements in the waist region 80 may have a smallercross sectional area than a plurality of elastic elements in the hipregion 82 but larger cross sectional area than a plurality of elasticelements in the leg region 84. For example, where the elastic elementscomprise elastic strands, the cross sectional area of the plurality ofelastic elements in the waist region 80, can vary from about 0.03 mm² toabout 0.1 mm². In contrast, the cross sectional area of the plurality ofelastic elements in the hip region 82 can be greater than about 0.1 mm²and less than or equal to about 0.4 mm², and the cross sectional area ofthe plurality of elastic elements in the leg region 84 can be less thanabout 0.03 mm² thereby providing the hip region 82 with a higher elasticmodulus than the waist and leg regions 80, 84 and a waist region 82 witha higher elastic modulus than the leg region 84.

In another embodiment, the structural differences impacting differentelastic modulus and stretchability between the regions may includeproviding a region with additional elastic elements impacting thefunction of that region. For example, a side panel 30 may comprise anelastic element which is present in the waist region, 80 hip region 82and leg region 84. In order to impact the functionality of the hipregion 82, an additional elastic element may be added to the hip region82 such that its functional properties differ with respect to the waistand leg regions 80, 84. Alternatively, an additional elastic element maybe added to the waist or leg regions 80, 84 or both and not the hipregion 82.

At this point, it is worth noting that any of the aforementioned methodsfor producing structural differences and corresponding functionaldifferences can be combined to provide the desired properties in a sidepanel 30.

Another embodiment where the functional differences between the waist,hip and leg regions 80, 82, 84 of the side panel 30 are attained bystructural differences includes increasing the bending modulus andcorresponding stiffness of the waist and/or leg region 80, 84 over thebending modulus and corresponding stiffness of the hip region 82 inorder to resist the first and second end edges 90, 92 in the waist orleg regions 80, 84 from folding or rolling over while at the same timeallowing the hip region 82 to flex and move freely with the wearer,reducing the chance of red marking on the wearer's skin. Bendingstiffness can be increased by adding an additional layer to the waistand/or leg regions 80, 84 adding rugosities to waist and/or leg regions80, 84 via elastic contraction where the rugosities are orientedsubstantially perpendicular to the longitudinal edges 50 and end edges52, or increasing the thickness of the existing material.

For another embodiment, the structural differences may result infunctional differences such as the force relaxation (set, etc.). Forinstance, it may be desirable for the force relaxation in the hip region82 to be lower than force relaxation in the waist and/or leg region 80,84 to allow the hip region 82 to effectively carry the waist anchoringtension and resist sagging. This may be accomplished by using a highquality elastomer such as a hydrogenated elastomer in the waist and legregions 80, 84. Hydrogenated elastomers have a lower force relaxation(less hysteresis) than non-hydrogenated elastomers.

In another embodiment the structural differences may impact functionaldifferences such as recovery rate, which is a measure of how rapidly theregion returns to an original relaxed length upon removal of a tensileforce. For instance, it may be desirable for the recovery rate in thewaist and/or leg regions 80, 84, be lower (i.e., slower) than the hipregion 82 to aid in fitting the article to the wearer by delaying tightleg/waist fit until after the article is on the wearer. Delayed recoveryresponse may be enabled by slow-recovery elastomers. Slow recoveryelastomers are described in U.S. application Ser. No. 11/144,508, filedJun. 3, 2005, titled “Absorbent Articles Comprising A Slow RecoveryElastomer” and U.S. application Ser. No. 11/144,497, filed Jun. 3, 2005,titled “Absorbent Articles Comprising A Slow Recovery Stretch Laminate”.

In another embodiment, the structural differences between the regionscan be made to impact the torsional modulus in the regions resulting ina greater torsional modulus in waist and/or leg regions 80, 84 than thetorsional modulus of the hip region 82 so as to reduce the tendency ofthe waist and leg regions to twist. Keeping the regions flat spreads thetension over a greater area rather than concentrating the tension on anarrow area which can cause red marking. Similar to bending stiffnessabove, torsional modulus can be increased by adding an additional layerto the waist and/or leg regions 80, 84, adding rugosities via elasticcontraction to the waist and leg regions where the rugosities areoriented substantially perpendicular to the end edge 52 or longitudinaledge 50, or increasing the thickness of the existing material.

In another embodiment, the structural differences between the regionsmay impact the compressive modulus. For instance, the compressivemodulus of the waist and/or leg regions 80, 84 may be lower than thecompressive modulus of the hip region 82. Since the waist and legregions are along the perimeter of the article, minimizing thecompressive modulus in these regions can increase the comfort levelalong the perimeter of the article. Compressive modulus can be reducedby increasing loft (thickness) of the material at a given basis weight,reducing the inter-layer bond density of laminated or layeredstructures, or choosing a material having an inherently lowercompressive modulus.

In another embodiment, the structural differences among the regions mayimpact the coefficient of friction resulting in a greater coefficient offriction in the waist and leg regions 80, 84 than that of the hip region82 so that the waist and leg regions form gaskets with zero orsignificantly reduced slippage in the waist and leg regions 80, 84.Alternatively, the coefficient of friction in the hip region 82 may behigher than the waist and leg regions 80, 84 to facilitate anchoring andsustained fit of the article on the wearer. COF may be reduced by a)application of a slip agent such as a lotion, a powder, or a low surfaceenergy material such as Teflon or b) use of a smooth material with fewmicro projections that could “snag” on rugosities in the skin. Examplesof suitable lotions include those described in U.S. Pat. No. 5,607,760entitled “Disposable Absorbent Article Having A Lotioned TopsheetContaining an Emollient and a Polyol Polyester Immobilizing Agent”issued to Roe on Mar. 4, 1997; U.S. Pat. No. 5,609,587 entitled “DiaperHaving A Lotion Topsheet Comprising A Liquid Polyol Polyester EmollientAnd An Immobilizing Agent” issued to Roe on Mar. 11, 1997; U.S. Pat. No.5,635,191 entitled “Diaper Having A Lotioned Topsheet Containing APolysiloxane Emollient” issued to Roe et al. on Jun. 3, 1997; U.S. Pat.No. 5,643,588 entitled “Diaper Having A Lotioned Topsheet” issued to Roeet al. on Jul. 1, 1997; U.S. Pat. No. 5,968,025 entitled “AbsorbentArticle Having a Lotioned Topsheet” issued to Roe et al. on Oct. 19,1999 and U.S. Pat No. 6,716,441 entitled “Compositions for the efficientrelease of active ingredients” issued to Osborne on Apr. 6, 2004.

In another embodiment, the structural differences may affect thefunctionality of the waist hip and leg regions 80, 82, 84 by influencingthe surface energy of one or more of the regions. Surface energy refersto the activity of the surface, such as the positive, negative or zerocharge of the surface which affects how other substances interact withthe surface. For instance, surface energy can effect how fluids spreadon the surface or adhere to the surface. Surface energy differencescould result from coating one portion of the ear with a Teflon-likematerial or silicone coating to provide a barrier to urine while theuntreated portion would provide better adherence for ink printing.Examples of coatings affecting surface energy include those described inapplication Ser. No. 11/055,743 filed Feb. 2, 2005 titled “HydrophobicSurface Coated Absorbent Articles and Associated Methods”.

Structural differences between the waist, hip, and leg regions 80, 82,84 can also influence visual aspects of the regions. In addition tostructure, visual differences between the regions can also be influencedby colors, textures, patterns, thickness, opacity, reflectivity, sheen,rugosity size, rugosity spacing, and rugosity frequency. Visualdifferences between the waist, hip, and leg regions 80, 82, 84 cancontribute to a garment-like appearance and/or provide an aid in fittingthe diaper to the wearer.

A garment-like look can be accomplished by making the regions appearcloth-like. For instance, the waist and leg regions 80, 84 of the sidepanel 30 can be made to look like seams while the hip region 82 is madeto appear as a cloth like fabric panel. Such visual distinctiveness canbe accomplished by adding color, patterns and/or layers of elasticmaterial producing visible gathers or rugosities via elasticcontraction.

In one embodiment, structural differences can be introduced to influencevisual differences as well as functional differences. For instance,elastic materials can be prestrained and attached to the waist region80, hip region 82 and leg region 84 at different levels of strainproducing different visible gathers or rugosities to further distinguishthe appearance of each of the regions while at the same time provideelastic properties desirable for each of the regions.

In addition, the visual differences between the waist, hip and legregions 80, 82, 84 can be combined with the aforementioned structuraland functional differences in order to a) provide an indication of whereto grasp the side panel in order to stretch it during application, b)make the leg and waist regions easier to distinguish to aid inapplication, c) provide a visually appealing pattern (e.g., racingstripes, etc.) to a child wearer, d) provide an indication of the frontvs. the back of the article, e) provide intuitive instructions to thecaregiver to facilitate application or removal of the article, and/or f)coordinate with other graphics on the chassis body.

Structural differences and corresponding functional and visualdifferences between the waist, hip and leg regions 80, 82, 84 of theside panels 30 can be influenced by other components of the diaper. Forinstance, as described hereunder, elastic waist features and legelastics can be made to extend into the waist and leg regions of theside panel to enhance the distribution of forces about the wearer aswell as provide continuous seams that appear more garment-like.

The diaper 20 may comprise at least one elastic waist feature 34 thathelps to provide improved fit and containment. The elastic waist feature34 is generally intended to elastically expand and contract todynamically fit the wearer's waist. The elastic waist feature 34preferably extends at least longitudinally outwardly from at least onewaist edge 62 of the absorbent core 28 and generally forms at least aportion of the end edge 52 of the diaper 20. Disposable diapers areoften constructed so as to have two elastic waist features, onepositioned in the first waist region 36 and one positioned in the secondwaist region 38. Further, while the elastic waist feature 34 or any ofits constituent elements may comprise one or more separate elementsaffixed to the diaper 20, the elastic waist feature 34 may beconstructed as an extension of other elements of the diaper 20, such asthe backsheet 26, the topsheet 24, or both the backsheet 26 and thetopsheet 24.

The elastic waist feature 34 in the second waist region 38 provides anextensible member that provides a more comfortable and contouring fit byinitially conformably fitting the diaper to the wearer and sustainingthis fit throughout the time of wear well past when the diaper has beenloaded with exudates since the extensible waist feature, particularly inthe back portion of the diaper allows the diaper to expand and,preferably, to contract. Further, the elastic waist feature 34 in thesecond waist region 38 develops and maintains wearing forces (tensions)that enhance the tensions developed and maintained by the closure systemto maintain the diaper on the wearer and enhance the fit of the diaper20 about the waist of the wearer. The elastic waist feature 34 in thesecond waist region 38 further provides more effective application ofthe diaper 20 since even if the caregiver pulls one side of the elasticwaist feature farther than the other during application(asymmetrically), the diaper will “self-adjust” during wear.

The elastic waist feature 34 may be attached to the outer, garmentfacing surface of the backsheet; the body facing surface of the topsheetor both. In addition the elastic waist feature may be attached betweenthe topsheet and the backsheet, or wrapped around the end edges 52 ofthe diaper 20 and attached to both the body-facing surface of thetopsheet and the garment-facing surface of the backsheet.

The elastic waist feature 34 may be constructed in a number of differentconfigurations. For instance, the elastic waist feature 34 may comprisea laminate structure consisting of a single layer of nonwoven with anelastomeric material attached covering a full width dimension of thenonwoven or only a portion of the width. The elastomeric material mayinclude an elastomer extruded onto the nonwoven or a film that is, gluedto the nonwoven. Alternatively, the elastic waist feature 34 maycomprise a laminate structure comprising two layers of nonwoven withelastomeric strands disposed therebetween covering the full width of thelaminate or only a portion of the width. In addition, the elastic waistfeature 34 may be constructed according to U.S. Pat. No. 4,515,595issued to Kievit et al. on May 7, 1985; U.S. Pat. No. 4,710,189 issuedto Lash on Dec. 1, 1987; U.S. Pat. No. 5,151,092 issued to Buell on Sep.9, 1992; and U.S. Pat. No. 5,221,274 issued to Buell on Jun. 22, 1993.Other suitable waist configurations may include waist cap features suchas those described in U.S. Pat. No. 5,026,364 issued to Robertson onJun. 25, 1991 and U.S. Pat. No. 4,816,025 issued to Foreman on Mar. 28,1989.

The diaper 20 can also comprise extensible leg cuffs 32 for providingimproved containment of liquids and other body exudates. Each extensibleleg cuff 32 may comprise several different embodiments, for reducing theleakage of body exudates in the leg regions. (The leg cuff can be and issometimes also referred to as leg bands, leg flaps, barrier cuffs, orelastic cuffs.) The extensible leg cuffs 32 may be attached to theouter, garment facing surface of the backsheet; the body facing surfaceof the topsheet or both. In addition, the extensible leg cuffs 32 may beattached between the topsheet and the backsheet, or wrapped around thelongitudinal side edges 50 of the diaper 20 and attached to both thebody-facing surface of the topsheet and the garment-facing surface ofthe backsheet.

Like the elastic waist feature 34, the extensible leg cuffs 32 may beconstructed in a number of different configurations. For instance, theextensible leg cuffs 32 may comprise a laminate structure consisting ofa single layer of nonwoven with an elastomeric material attachedcovering a full width dimension of the nonwoven or only a portion of thewidth. The elastomeric material may include an extruded elastic strandlaminate comprising prestrained extruded elastic strands laminated to anonwoven or a film that is subsequently glued to the garment facingsurface of the backsheet along the longitudinal edges 50 of the diaper20 and allowed to relax to form a shirred or corrugated structure.Alternatively, the extensible leg cuffs 32 may comprise a laminatestructure comprising two layers of nonwoven with prestrained extrudedelastic strands laminated between the two layers of nonwoven coveringthe full width of the laminate or only a portion of the width. Thelaminate structure can be subsequently glued to the garment facingsurface of the backsheet along the longitudinal edges 50 of the diaper20 while in the prestrained condition so that a shirred or corrugatedstructure is formed once tension is removed from the laminate allowingit to relax. In addition, the extensible leg cuffs 32 may comprise aprestrained elastic strand or strands bonded in a prestrained conditionbetween a portion of the backsheet or topsheet that is folded over.

In addition, the extensible leg cuffs 32 may be constructed according toone or more of the patents described hereunder. U.S. Pat. No. 3,860,003entitled “Contractable Side Portions For a Disposable Diaper”, issued toBuell on Jan. 14, 1975, describes a disposable diaper providing acontractible leg opening having a leg flap and one or more elasticmembers to provide an elasticized leg cuff (gasketing cuff). U.S. Pat.No. 4,909,803 entitled “Disposable Absorbent Article Having ElasticizedFlaps” issued to Aziz & Blaney on Mar. 20, 1990, describes a disposablediaper having “stand-up” elasticized flaps (barrier cuffs) to improvethe containment of the leg regions. U.S. Pat. No. 4,695,278 entitled“Absorbent Article Having Dual Cuffs” issued to Lawson on Sep. 22, 1987,describes a disposable diaper having dual cuffs including a gasketingcuff and a barrier cuff. U.S. Pat. No. 4,704,115 entitled “DisposableWaste Containment Garment” issued to Buell on Nov. 3, 1987, discloses adisposable diaper or incontinent garment having side-edge-leakage-guardgutters configured to contain free liquids within the garment. U.S. Pat.No. 5,032,120 entitled “Disposable Absorbent Article Having Improved LegCuffs” issued to Freeland & Allen on Jul. 16, 1991, discloses anabsorbent article having leg cuffs having a relatively low ultimatecontact force at relatively high elongations accomplished, for example,by low contact force differential material. U. S. Pat. No. 5, 087,255entitled “Absorbent Article Having Inflected Barrier Cuffs” issued toSims on Feb. 11, 1992, discloses an absorbent article having inflectedbarrier cuffs with the distal edge positioned outboard of the proximaledge in one waist region and inboard in the other to provide better fitabout the hips/buttocks.

FIG. 3 depicts a diaper 20 in a fastened configuration illustrating howvisual differences between the waist, hip and leg regions 80, 82, 84 notonly exhibit a garment-like look but also provide functional attributesenabling the caregiver to properly align the diaper on the wearer duringfitting. As shown, the leg region 84 of the side panel 30 can be made tomatch the longitudinal edges 50 and the waist region 80 can be made tomatch the end edges 52 in the first and second waist regions 36, 38.Once the diaper 20 is donned on a wearer, the waist regions 80 of theside panels 30 align with the end edges 52 in the first and second waistregions 36, 38 forming a complete 360° waist band encircling the waistopening 74 of the diaper 20. At the same time, the leg regions 84 of theside panels 30 align with the longitudinal edges 50 of the diaper toform 360° leg bands encircling the leg openings 72.

In addition to visual distinctions, structural differences may beintroduced to further enhance the visual features and to provideadditional functional attributes of the different regions. For instance,the elastic waist feature 34 in the second waist region 38 can be madeto extend into one or both of the side panels 30 partially or fullycovering the waist region 80 in one or both of the side panels 30. Forthe embodiment shown in FIG. 3, the elastic waist feature 34 in thesecond waist region 38 is shown fully covering the waist region 80 ineach of the side panels 30 such that the combination of the elasticwaist feature 34 in the second waist region 38 of the diaper and thewaist region 80 in each of the side panels 30 aligns with the elasticwaist feature 34 in the first waist region 36 of the diaper forming a360° elastic waist about the waist opening 74 when the diaper 20 isdonned on a wearer.

Similarly, the extensible leg cuffs 32 can be made to extend into theleg region 84 of one or both of the side panels 30 partially or fullycovering the leg region 84 in one or both of the side panels 30. Asshown in FIG. 3, the extensible leg cuffs 32 can be made to fully coverthe leg region 84 in each of the side panels 30 such that thecombination of the leg region 84 in each of the side panels 30 and theextensible leg cuffs 32 form complete 360° leg elastics about each ofthe leg openings 72. For this embodiment, the extensible leg cuffs 32and the leg regions 84 in each of the side panels can includeaforementioned visual features to appear as garment-like seams about theleg openings.

For the embodiment illustrated in FIG. 3, the hip region 82 in each ofthe side panels 30 may comprise a zero-strain elastomeric laminateincluding an elastic film disposed between two nonwoven layers. Thezero-strain elastomeric laminate may terminate at the waist and legregions 80, 84 or may extend at least partially into the waist and legregions 80, 84. In the latter case, the waist and leg regions 80, 84 maybe disposed on the garment facing side of the zero-strain elastomericlaminate, the body-facing side of the zero strain elastomeric laminate,or both. Alternatively, the waist and leg regions 80, 84 may wrap aroundthe first and second end edges 90, 92, respectively, of the side panels30 and overlap the zero-strain elastomeric laminate.

FIG. 4 depicts a pant style diaper 220 illustrating how visualdistinctions and structural differences between the leg, hip, and legregions 280, 282, 284 can be made to enhance fit as well as agarment-like look. As shown in FIG. 4, the waist regions 280 of the sidepanels 230 comprise a continuation of a waist band 210 proximate the endedges 252 in the first waist region 236. The waist band 210 can includean elastic waist feature 234 extending into, and partially or fullycovering the waist region 280 in each of the side panels 230. Althoughnot shown, the waist regions 280 of the side panels 230 can alsocomprise a continuation of a waist band and/or elastic waist featureproximate the end edges in the second waist regions forming, incombination with the elastic waist feature 234 in the first waist region236, a 360° waist band encircling the waist opening 274. In addition, asshown in FIG. 4, the leg regions 284 of the side panels 230 can comprisea continuation of leg bands 212 proximate the longitudinal edges 250 inthe crotch region 237 of the pant style diaper 220 forming 360° legbands 212 encircling the leg openings 272. The leg bands 212 may alsoinclude extensible leg cuffs 232 partially or fully covering the legregions 284 in each of the side panels 230.

Other components of the chassis 22 include the backsheet 26, thetopsheet 24 and the core 28. The backsheet 26 is generally that portionof the diaper 20 positioned adjacent garment facing surface of theabsorbent core 28 which prevents the exudates absorbed and containedtherein from soiling articles which may contact the diaper 20, such asbed sheets and undergarments. In preferred embodiments, the backsheet 26is impervious to liquids (e.g., urine) and comprises a thin plastic filmsuch as a thermoplastic film having a thickness of about 0.012 mm (0.5mil) to about 0.051 mm (2.0 mils). Suitable backsheet films includethose manufactured by Tredegar Corporation, based in Richmond, Va., andsold under the trade name CPC2 film. Other suitable backsheet materialsmay include breathable materials which permit vapors to escape from thediaper 20 while still preventing exudates from passing through thebacksheet 26. Exemplary breathable materials may include materials suchas woven webs, nonwoven webs, composite materials such as film-coatednonwoven webs, microporous films such as manufactured by Mitsui ToatsuCo., of Japan under the designation ESPOIR NO and by TredegarCorporation of Richmond, Va. and sold under the designation EXAIRE, andmonolithic films such as manufactured by Clopay Corporation, Cincinnati,Ohio under the name HYTREL blend P18-3097. Some breathable compositematerials are described in greater detail in PCT Application No. WO95/16746 published on Jun. 22, 1995 in the name of E. I. DuPont; U.S.Pat. No. 5,938,648 issued on Aug. 17, 1999 to LaVon et al.; U.S. Pat.No. 5,865,823 issued on Feb. 2, 1999 in the name of Curro; and U.S. Pat.No. 5,571,096 issued to Dobrin et al. on Nov. 5, 1996.

The backsheet 26, or any portion thereof, may be elastically extensiblein one or more directions. In one embodiment, the backsheet 26 maycomprise a structural elastic-like film (“SELF”) web. A structuralelastic-like film web is an extensible material that exhibits anelastic-like behavior in the direction of elongation without the use ofadded elastic materials and is described in more detail in U.S. Pat. No.5,518,801 entitled “Web Materials Exhibiting Elastic-Like Behavior”issued to Chappell, et al. on May 21, 1996. In alternate embodiments,the backsheet 26 may comprise elastomeric films, foams, strands, orcombinations of these or other suitable materials with nonwovens orsynthetic films.

The backsheet 26 may be joined to the topsheet 24, the absorbent core 28or any other element of the diaper 20 by any attachment means known inthe art. For example, the attachment means may include a uniformcontinuous layer of adhesive, a patterned layer of adhesive, or an arrayof separate lines, spirals, or spots of adhesive. One preferredattachment means comprises an open pattern network of filaments ofadhesive as disclosed in U.S. Pat. No. 4,573,986 entitled “DisposableWaste-Containment Garment”, which issued to Minetola et al. on Mar. 4,1986. Other suitable attachment means include several lines of adhesivefilaments which are swirled into a spiral pattern, as is illustrated bythe apparatus and methods shown in U.S. Pat. No. 3,911,173 issued toSprague, Jr. on Oct. 7, 1975; U.S. Pat. No. 4,785,996 issued to Ziecker,et al. on Nov. 22, 1978; and U.S. Pat. No. 4,842,666 issued to Wereniczon Jun. 27, 1989. Adhesives which have been found to be satisfactory aremanufactured by H. B. Fuller Company of St. Paul, Minn. and marketed asHL-1620 and HL 1358-XZP. Alternatively, the attachment means maycomprise heat bonds, pressure bonds, ultrasonic bonds, dynamicmechanical bonds, or any other suitable attachment means or combinationsof these attachment means as are known in the art.

The topsheet 24 is preferably positioned adjacent body surface of theabsorbent core 28 and may be joined thereto and/or to the backsheet 26by any attachment means known in the art. Suitable attachment means aredescribed above with respect to means for joining the backsheet 26 toother elements of the diaper 20. In one preferred embodiment of thepresent invention, the topsheet 24 and the backsheet 26 are joineddirectly to each other in some locations and are indirectly joinedtogether in other locations by directly joining them to one or moreother elements of the diaper 20.

The topsheet 24 is preferably compliant, soft-feeling, andnon-irritating to the wearer's skin. Further, at least a portion of thetopsheet 24 is liquid pervious, permitting liquids to readily penetratethrough its thickness. A suitable topsheet may be manufactured from awide range of materials, such as porous foams, reticulated foams,apertured plastic films, or woven or nonwoven materials of naturalfibers (e.g., wood or cotton fibers), synthetic fibers (e.g., polyesteror polypropylene fibers), or a combination of natural and syntheticfibers. If the topsheet 24 includes fibers, the fibers may be spunbond,carded, wet-laid, meltblown, hydroentangled, or otherwise processed asis known in the art. One suitable topsheet 24 comprising a web ofstaple-length polypropylene fibers is manufactured by Veratec, Inc., aDivision of International Paper Company, of Walpole, Mass. under thedesignation P-8.

Suitable formed film topsheets are described in U.S. Pat. No. 3,929,135,entitled “Absorptive Structures Having Tapered Capillaries” issued toThompson on Dec. 30, 1975; U.S. Pat. No. 4,324,246 entitled “DisposableAbsorbent Article Having A Stain Resistant Topsheet” issued to Mullane,et al. on Apr. 13, 1982; U.S. Pat. No. 4,342,314 entitled “ResilientPlastic Web Exhibiting Fiber-Like Properties” issued to Radel, et al. onAug. 3, 1982; U.S. Pat. No. 4,463,045 entitled “Macroscopically ExpandedThree-Dimensional Plastic Web Exhibiting Non-Glossy Visible Surface andCloth-Like Tactile Impression” issued to Ahr, et al. on Jul. 31, 1984;and U.S. Pat. No. 5,006,394 “Multilayer Polymeric Film” issued to Bairdon Apr. 9, 1991. Other suitable topsheets may be made in accordance withU.S. Pat. Nos. 4,609,518 and 4,629,643 issued to Curro et al. on Sep. 2,1986 and Dec. 16, 1986, respectively. Such formed films are availablefrom The Procter & Gamble Company of Cincinnati, Ohio as “DRI-WEAVE” andfrom Tredegar Corporation, based in Richmond, Va., as “CLIFF-T.”

Preferably, at least a portion of the topsheet 24 is made of ahydrophobic material or is treated to be hydrophobic in order to isolatethe wearer's skin from liquids contained in the absorbent core 28. Ifthe topsheet 24 is made of a hydrophobic material, preferably at least aportion of the upper surface of the topsheet 24 is treated to behydrophilic so that liquids will transfer through the topsheet morerapidly. The topsheet 24 can be rendered hydrophilic by treating it witha surfactant or by incorporating a surfactant into the topsheet.Suitable methods for treating the topsheet 24 with a surfactant includespraying the topsheet 24 material with the surfactant and/or immersingthe material into the surfactant. A more detailed discussion of such atreatment and hydrophilicity is contained in U.S. Pat. No. 4,988,344entitled “Absorbent Articles with Multiple Layer Absorbent Layers”issued to Reising, et al. on Jan. 29, 1991 and U.S. Pat. No. 4,988,345entitled “Absorbent Articles with Rapid Acquiring Absorbent Cores”issued to Reising on Jan. 29, 1991. A more detailed discussion of somesuitable methods for incorporating a surfactant in the topsheet 24 canbe found in U.S. Statutory Invention Registration No. H1670 published onJul. 1, 1997 in the names of Aziz et al. Alternatively, the topsheet 24may include an apertured web or film which is hydrophobic. This may beaccomplished by eliminating the hydrophilizing treatment step from theproduction process and/or applying a hydrophobic treatment to thetopsheet 24, such as a polytetraflouroethylene compound like SCOTCHGUARDor a hydrophobic lotion composition, as described below. In suchembodiments, it is preferred that the apertures be large enough to allowthe penetration of aqueous fluids like urine without significantresistance.

The absorbent core 28 may comprise any absorbent material which isgenerally compressible, conformable, non-irritating to the wearer'sskin, and capable of absorbing and retaining liquids such as urine andother certain body exudates. The absorbent core 28 may be manufacturedin a wide variety of sizes and shapes (e.g., rectangular, hourglass,“T”-shaped, asymmetric, etc.) and may comprise a wide variety ofliquid-absorbent materials commonly used in disposable diapers and otherabsorbent articles such as comminuted wood pulp, which is generallyreferred to as airfelt. Examples of other suitable absorbent materialsinclude creped cellulose wadding; meltblown polymers, including coform;chemically stiffened, modified or cross-linked cellulosic fibers;tissue, including tissue wraps and tissue laminates; absorbent foams;absorbent sponges; superabsorbent polymers; absorbent gelling materials;or any other known absorbent material or combinations of materials.

The configuration and construction of the absorbent core 28 may also bevaried (e.g., the absorbent core(s) or other absorbent structure(s) mayhave varying caliper zones, hydrophilic gradient(s), a superabsorbentgradient(s), or lower average density and lower average basis weightacquisition zones; or may comprise one or more layers or structures).Exemplary absorbent structures for use as the absorbent core 28 aredescribed in U.S. Pat. No. 4,610,678 entitled “High-Density AbsorbentStructures” issued to Weisman et al. on Sep. 9, 1986; U.S. Pat. No.4,673,402 entitled “Absorbent Articles With Dual-Layered Cores” issuedto Weisman et al. on Jun. 16, 1987; U.S. Pat. No. 4,834,735 entitled“High Density Absorbent Members Having Lower Density and Lower BasisWeight Acquisition Zones” issued to Alemany et al. on May 30, 1989; U.S.Patent 4,888,231 entitled “Absorbent Core Having A Dusting Layer” issuedto Angstadt on Dec. 19, 1989; U.S. Pat. No. 5,137,537 entitled“Absorbent Structure Containing Individualized, Polycarboxylic AcidCrosslinked Wood Pulp Cellulose Fibers” issued to Herron et al. on Aug.11, 1992; U.S. Pat. No. 5,147,345 entitled “High Efficiency AbsorbentArticles For Incontinence Management” issued to Young et al. on Sep. 15,1992; U.S. Pat. No. 5,342,338 entitled “Disposable Absorbent Article ForLow-Viscosity Fecal Material” issued to Roe on Aug. 30, 1994; U.S. Pat.No. 5,260,345 entitled “Absorbent Foam Materials For Aqueous Body Fluidsand Absorbent Articles Containing Such Materials” issued to DesMarais etal. on Nov. 9, 1993; U.S. Pat. No. 5,387,207 entitled “Thin-Until-WetAbsorbent Foam Materials For Aqueous Body Fluids And Process For MakingSame” issued to Dyer et al. on Feb. 7, 1995; and U.S. Pat. No. 5,625,222entitled “Absorbent Foam Materials For Aqueous Fluids Made From HighInternal Phase Emulsions Having Very High Water-To-Oil Ratios” issued toDesMarais et al. on Jul. 22, 1997.

The diaper 20 may also include a fastening system 40. The fasteningsystem 40 preferably maintains the first waist region 36 and the secondwaist region 38 in a configuration so as to provide lateral tensionsabout the circumference of the diaper 20 to hold the diaper 20 on thewearer. The fastening system 40 preferably comprises a fastener such astape tabs, hook and loop fastening components, interlocking fastenerssuch as tabs & slots, buckles, buttons, snaps, and/or hermaphroditicfastening components, although any other known fastening means aregenerally acceptable. Some exemplary surface fastening systems aredisclosed in U.S. Pat. No. 3,848,594 entitled “Tape Fastening System forDisposable Diaper” issued to Buell on Nov. 19, 1974; U.S. Pat. No.4,662,875 B1 entitled “Absorbent Article” issued to Hirotsu et al. onMay 5, 1987; U.S. Pat. No. 4,846,815 entitled “Disposable Diaper HavingAn Improved Fastening Device” issued to Scripps on Jul. 11, 1989; U.S.Pat. No. 4,894,060 entitled “Disposable Diaper With Improved HookFastener Portion” issued to Nestegard on Jan. 16, 1990; U.S. Pat. No.4,946,527 entitled “Pressure-Sensitive Adhesive Fastener And Method ofMaking Same” issued to Battrell on Aug. 7, 1990; the herein beforereferenced U.S. Pat. No. 5,151,092 issued to Buell on Sep. 9, 1992; andU.S. Pat. No. 5,221,274 issued to Buell on Jun. 22, 1993. An exemplaryinterlocking fastening system is disclosed in co-pending U.S. Pat. No.6,432,098 entitled “Absorbent Article Fastening Device” in the names ofKline et al. issued on Aug. 13, 2002. The fastening system 40 may alsoprovide a means for holding the article in a disposal configuration asdisclosed in U.S. Pat. No. 4,963,140 issued to Robertson et al. on Oct.16, 1990. The fastening system may also include primary and secondaryfastening systems, as disclosed in U.S. Pat. No. 4,699,622 entitled“Disposable Diaper Having An Improved Side Closure” issued to Toussantet al. on Oct. 13, 1987.

TEST METHODS

Hysteresis Test for Elastic Properties

Overview

This test measures: a) elastic resistance (load at 25% elongation), b)force relaxation, and c) percent set of a side panel region. Ideally,the sample dimension should be 2.54 cm wide×5.08 cm long, with thedirection of stretch being the long dimension. Furthermore, ideally, thegage length should be 2.54 cm. Because of the variety of geometries thatthe regions can be in, it may be necessary to use a different samplewidth and/or length and normalize the results to the ideal sample basis.Once a sample has been prepared, it is stretched according to apredefined regimen to provide data for property determination.

Apparatus

-   Tensile Tester: A commercial constant rate of extension tensile    tester from Instron Engineering Corp., Canton, Mass. or SINTECH-MTS    Systems Corporation, Eden Prairie, Minn. (or a comparable tensile    tester) may is suitable. The instrument is interfaced with a    computer for controlling the test speed and other test parameters,    and for collecting, calculating and reporting the data.-   Load Cell Choose the jaws and load cell suitable for the test; the    jaws should be wide enough to fit the sample, typically 2.54 cm jaws    are used; the load cell is chosen so that the expected tensile    response from the sample tested will be between 25% and 75% of the    capacity of the load cells or the load range used, typically a 1 kN    load cell, is used;-   Sample Cutter The specific sample cutter is defined by the desired    sample width. Suitable cutters are available from Thwing-Albert    Instrument Co. of Philadelphia, Pa. For a 2.54 cm wide sample a    Model JDC 1-10 is suitable.    Sample Preparation

Cut waist, hip and leg regions from the side panel along the boundarydefined by the visible or structural difference. Cut a sample of eachregion that is 2.54 cm wide by 5.08 cm long from within an individualregion. If an individual region is smaller than these dimensions, thesample should comprise the entire region. Orient the sample in the jawsto ensure that the sample is stretched in the longitudinal direction ofthe region. If the force from an individual region is too small tomeasure on the tensile tester, several samples from identical regiontaken from multiple products can be pulled collectively in between thegrips of the tensile tester, and the data normalized to an individualregion basis.

Method

The hysteresis is measured under standard laboratory conditions (25°C±2° C. and relative humidity of about 50%±2.0%).

The procedure for determining hysteresis of an elastomeric memberinvolves the following steps:

-   1. Calibrate the tester according to the manufacturer's    instructions.-   2. Set the gauge length at 2.54 cm or as appropriate for the sample    being tested; set the slack preload at 0.05 N.-   3. Place the sample in the flat surface of the jaws such that the    longitudinal centerline of the sample is substantially parallel to    the gauge length direction.-   4. Set the crosshead speed at a constant speed of 25.4 cm/min.-   5. Initiate crosshead motion, the tester begins to record load and    strain data simultaneously. The hysteresis test specifically    involves the following steps:    -   a) elongate the sample to 25% strain at a constant rate of 25.4        cm/min—record the force at 25% elongation;    -   b) allow the sample to remain at this strain for 2        minutes—record the force at the start and end of the 2 minute        period;    -   c) return the sample to 0% strain at a constant rate of 25.4        cm/min;    -   d) allow sample to remain at this strain for 1 minute; and    -   e) elongate the sample to 0.1 N load at a constant rate of 5.08        cm/min—record the strain at 0.1N (i.e., a force sufficient to        remove slack but low enough to impart, at most, insubstantial        stretch to the sample).        Calculations and Reported Results-   1. From the data collected in step 5(a), the load at 25% strain is    reported as the elastic resistance of the material.-   2. From the data collected in step 5(b), the force relaxation is    determined by the load at the beginning and at the end of the 2    minutes hold time using the following formula:

${\%\mspace{14mu}{Stress}\mspace{14mu}{Relaxation}\mspace{14mu}{at}\mspace{14mu}{time}},{t = {\frac{\left\lbrack {\left( {{initial}\mspace{14mu}{load}} \right) - \left( {{{load}\mspace{14mu}{at}\mspace{14mu}{time}},t} \right)} \right\rbrack}{{initial}\mspace{14mu}{load}} \times 100}}$

-   3. From the data collected in step 5(e), the % set is calculated    using the following formula:

${{Percent}\mspace{14mu}{Set}} = {\left\lbrack {\left( \frac{{Strain}\mspace{14mu}{Recorded}\mspace{14mu}{at}\mspace{14mu} 5(e)}{{Gage}\mspace{14mu}{Length}} \right) - 1} \right\rbrack \times 100}$

-   4. Report the average results from three replicate samples for each    region tested.    Available Strain

This is intended to determine the Available Strain of a sample. TheAvailable Strain is the point at which there is an inflection in theforce-elongation curve, beyond which point there is a rapid increase inthe amount of force required to elongate the sample further. Anexemplary force (F(N/cm))−elongation (E(%)) curve is shown as FIG. 5. Asshown therein, available strain is determined from force elongationcurve 720 as the intersection point 720 b of linear extrapolations ofthe stage 1 portion of the curve 720 a and the stage 2 portion of thecurve 720 c.

Method

-   1. Samples are prepared according to the Hysteresis Test described    above.-   2. Repeat steps 1-4 of the Hysteresis Test.-   3. Initiate crosshead motion. The tester begins to record load    versus strain (percent elongation) data simultaneously.-   4. Continue elongating the sample until either:    -   a) the sample breaks; or    -   b) the force limit of the load cell is reached.-   5. Plot the force/elongation data to create a curve similar to that    shown in FIG. 5.-   6. Extrapolate the stage 1 and stage 2 portions as shown to    determine the available strain.-   7. Report the average results from three replicate samples for each    region tested.

All documents cited in the Detailed Description of the Invention are, inrelevant part, incorporated herein by reference; the citation of anydocument is not to be construed as an admission that it is prior artwith respect to the present invention. To the extent that any meaning ordefinition of the term in a document incorporated by reference, themeaning or definition assigned to the term in this written documentshall govern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A disposable pant style absorbent article to beworn about the lower torso of a wearer, the disposable pant styleabsorbent article including an inner body facing surface, an outergarment facing surface, a first waist region, a second waist region, anda crotch region interposed between the first waist region and the secondwaist region, a waist opening and a pair of leg openings, the disposablearticle comprising: a chassis having first and second side edges andfirst and second transverse end edges, said chassis comprising: atopsheet; a backsheet; and an absorbent core disposed between thetopsheet and the backsheet; a first elasticized panel joined to saidchassis and disposed in said first waist region, said first elasticizedpanel comprising a first stretch laminate, and three regions including awaist region, a hip region, and a leg region; a first elastic waistfeature disposed in the first waist region wherein the first waistfeature extends outboard of at least one of said first and second sideedges of said chassis into the waist region of said first elasticizedpanel such that said first elastic waist feature overlaps with at leasta portion of said first stretch laminate of said first elasticizedpanel; a second elasticized panel joined to said chassis and disposed insaid second waist region, said second elasticized panel comprising asecond stretch laminate, and three regions including a waist region, ahip region, and a leg region; and a second elastic waist featuredisposed in the second waist region wherein the second waist featureextends outboard of at least one of said first and second side edges ofsaid chassis into the waist region of said second elasticized panel suchthat said second elastic waist feature overlaps with at least a portionof said second stretch laminate of said second elasticized panel,wherein at least one of said first, and second stretch laminatescomprises an elastic film joined to at least one layer of a nonwovenmaterial and wherein said first elasticized panel is joined to saidsecond elasticized panel.
 2. The disposable pant style absorbent articleaccording to claim 1 wherein each of said first and second elastic waistfeatures comprises a plurality of elastomeric strands.
 3. The disposablepant style absorbent article according to claim 2 wherein said pluralityof elastomeric strands are disposed between two layers of a nonwovenmaterial.
 4. The disposable pant style absorbent article according toclaim 1 wherein said first and second elastic waist features encirclesaid waist opening.
 5. The disposable pant style absorbent articleaccording to claim 1 wherein said first and second stretch laminatescomprise an elastic material that is joined to a nonwoven material whilesaid elastic material is in a stretched configuration.
 6. The disposablepant style absorbent article according to claim 5 wherein said elasticmaterial is stretched at least 25% of its relaxed length when it isjoined to said nonwoven material.
 7. The disposable pant style absorbentarticle according to claim 1 wherein each of said first, and secondstretch laminates comprises an elastic film.
 8. The disposable pantstyle absorbent article according to claim 7 wherein said elastic filmcomprises a material chosen from at least one of polypropylene,polyethylene, polyolefins, styrene-isoprene-styrene, andstyrene-butadiene-styrene.
 9. The disposable pant style absorbentarticle according to claim 8 wherein said elastic film has a basisweight of from about 10 gsm to about 100 gsm.
 10. The disposable pantstyle absorbent article according to claim 1 further comprising at leasta first elastic strand that is disposed in the leg region of said firstelasticized panel.
 11. The disposable pant style absorbent articleaccording to claim 10 further comprising at least a second elasticstrand that is disposed in the leg region of said second elasticizedpanel.
 12. The disposable pant style absorbent article according toclaim 11 wherein said first elastic strand is joined to said leg regionof said first elasticized panel in a pre-strained configuration causingcorrugations of said first stretch laminate in said leg region when saidfirst strand relaxes.
 13. The disposable pant style absorbent articleaccording to claim 1 wherein the first elasticized panel includes innerand outer surfaces and wherein said first elastic waist feature isdisposed on said outer surface of said first elasticized panel.
 14. Thedisposable pant style absorbent article according to claim 1 furthercomprising a plurality of elastic strands disposed between said topsheetand said backsheet and forming first and second gasketing leg cuffsdisposed on opposite sides of the absorbent article.
 15. The disposablepant style absorbent article according to claim 14 further comprising atleast a first elastic strand that is disposed in the leg region of saidfirst elasticized panel and at least a second elastic strand that isdisposed in the leg region of said second elasticized panel.
 16. Thedisposable pant style absorbent article according to claim 15 whereinsaid first elastic strand that is disposed in the leg region of saidfirst elasticized panel, said elastic strands of said first gasketingcuff and said second elastic strand that is disposed in the leg regionof said second elasticized panel substantially encircle a first legopening.
 17. The disposable pant style absorbent article according toclaim 1 wherein said first waist feature extends to a longitudinal endedge of said first side panel and wherein said second waist featureextends to a longitudinal end edge of said second side panel such thatfirst and second waist features encircle said waist opening.
 18. Thedisposable pant style absorbent article according to claim 1 whereinsaid first and second elasticized panels are joined, at anon-refastenable bond.
 19. A disposable pant style absorbent article tobe worn about the lower torso of a wearer, the disposable pant styleabsorbent article including an inner body facing surface, an outergarment facing surface, a first waist region, a second waist region, anda crotch region interposed between the first waist region and the secondwaist region, a waist opening and a pair of openings, the disposablearticle comprising: a chassis having first and second side edges andfirst and second transverse end edges, said chassis comprising: atopsheet; a backsheet; and an absorbent core disposed between thetopsheet and the backsheet; a first elasticized panel joined to saidchassis and disposed in said first waist region, said first elasticizedpanel comprising a first stretch laminate, and three regions including awaist region, a hip region, and a leg region that are disposed outboardof at least one said first and second side edges of said chassis; atleast a first elastic strand that is disposed in the leg region of saidfirst elasticized panel and is outboard one of said first and secondside edges of said chassis; a first elastic waist feature disposed inthe first waist region wherein the first waist feature extends into thewaist region of said first elasticized panel such that said elasticwaist feature overlaps with at least a portion of said first stretchlaminate of said first elasticized panel, wherein said first elasticwaist features comprises a plurality of elastomeric strands; a secondelasticized panel joined to said chassis and disposed in said secondwaist region, said second elasticized panel comprising a second stretchlaminate, and three regions including a waist region, a hip region, anda leg region; and a second elastic waist feature disposed in the secondwaist region wherein the second waist feature extends into the waistregion of said second elasticized panel such that said second elasticwaist feature overlaps with at least a portion of said second stretchlaminate of said second elasticized panel wherein said second elasticwaist features comprises a plurality of elastomeric strands, wherein atleast one of said first, and second stretch laminates comprises anelastic film joined to at least one layer of a nonwoven material andwherein said first elasticized panel is joined to said secondelasticized panel.
 20. The disposable absorbent article according toclaim 19 further comprising at least a second elastic strand that isdisposed in the leg region of said second elasticized panel and isoutboard one of said side edges of said chassis.
 21. The disposable pantstyle absorbent article according to claim 19 wherein said first andsecond stretch laminates comprise an elastic material that is bonded toa nonwoven material while said elastic material is in a stretchedconfiguration.
 22. The disposable pant style absorbent article accordingto claim 21 wherein said elastic material is stretched at least 25% ofits relaxed length when it is bonded to said nonwoven material.
 23. Thedisposable pant style absorbent article according to claim 19 whereinsaid first waist feature extends outboard at least one of said first andsecond side edges to a longitudinal end edge of said first side paneland wherein said second waist feature extends outboard at least one ofsaid first and second side edges to a longitudinal end edge of saidsecond side panel such that first and second waist features encirclesaid waist opening.